Our colon contains trillions of bacterial cells which make up a unique ecosystem known as the gut microbiome. Other than letting in nutrients into the body and locking out harmful pathogens, the activities of your gut bacteria influences your brain a lot more than you might realise.
Take being under stress as an example. The body undergoes a variety of changes when it is exposed to stress. A great deal of energy and major resources get redirected to the muscles and brain. One of the body’s main responses to stress is to release cortisol, and that plays a big role in affecting the balance of the gut microbiome.